ENH: add support for operator() in crackfortran.

doc/release/upcoming_changes/15006.new_feature.rst

@@ -0,0 +1,7 @@
+crackfortran has support for operator and assignment overloading
+----------------------------------------------------------------
+``crackfortran`` parser now understands operator and assignement
+defintions in a module. They are added in the ``body`` list of the
+module which contains a new key ``implementedby`` listing the names
+of the subroutines or functions implementing the operator or
+assignment.

numpy/f2py/crackfortran.py

@@ -574,11 +574,16 @@ def readfortrancode(ffile, dowithline=show, istop=1):
 groupends = (r'end|endprogram|endblockdata|endmodule|endpythonmodule|'
              r'endinterface|endsubroutine|endfunction')
 endpattern = re.compile(
-    beforethisafter % ('', groupends, groupends, r'[\w\s]*'), re.I), 'end'
-endifs = r'(end\s*(if|do|where|select|while|forall|associate|block|critical|enum|team))|(module\s*procedure)'
+    beforethisafter % ('', groupends, groupends, r'.*'), re.I), 'end'
+endifs = r'end\s*(if|do|where|select|while|forall|associate|block|' + \
+         r'critical|enum|team)'
 endifpattern = re.compile(
     beforethisafter % (r'[\w]*?', endifs, endifs, r'[\w\s]*'), re.I), 'endif'
 #
+moduleprocedures = r'module\s*procedure'
+moduleprocedurepattern = re.compile(
+    beforethisafter % ('', moduleprocedures, moduleprocedures, r'.*'), re.I), \
+    'moduleprocedure'
 implicitpattern = re.compile(
     beforethisafter % ('', 'implicit', 'implicit', '.*'), re.I), 'implicit'
 dimensionpattern = re.compile(beforethisafter % (
@@ -727,7 +732,8 @@ def crackline(line, reset=0):
                 callpattern, usepattern, containspattern,
                 entrypattern,
                 f2pyenhancementspattern,
-                multilinepattern
+                multilinepattern,
+                moduleprocedurepattern
                 ]:
         m = pat[0].match(line)
         if m:
@@ -797,6 +803,8 @@ def crackline(line, reset=0):
         expectbegin = 0
     elif pat[1] == 'endif':
         pass
+    elif pat[1] == 'moduleprocedure':
+        analyzeline(m, pat[1], line)
     elif pat[1] == 'contains':
         if ignorecontains:
             return
@@ -886,6 +894,9 @@ def appenddecl(decl, decl2, force=1):
     r'\s*(?P<this>(@\(@.*?@\)@|\*[\d*]+|\*\s*@\(@.*?@\)@|))(?P<after>.*)\Z', re.I)
 nameargspattern = re.compile(
     r'\s*(?P<name>\b[\w$]+\b)\s*(@\(@\s*(?P<args>[\w\s,]*)\s*@\)@|)\s*((result(\s*@\(@\s*(?P<result>\b[\w$]+\b)\s*@\)@|))|(bind\s*@\(@\s*(?P<bind>.*)\s*@\)@))*\s*\Z', re.I)
+operatorpattern = re.compile(
+    r'\s*(?P<scheme>(operator|assignment))'
+    r'@\(@\s*(?P<name>[^)]+)\s*@\)@\s*\Z', re.I)
 callnameargspattern = re.compile(
     r'\s*(?P<name>\b[\w$]+\b)\s*@\(@\s*(?P<args>.*)\s*@\)@\s*\Z', re.I)
 real16pattern = re.compile(
@@ -908,6 +919,10 @@ def _resolvenameargspattern(line):
     m1 = nameargspattern.match(line)
     if m1:
         return m1.group('name'), m1.group('args'), m1.group('result'), m1.group('bind')
+    m1 = operatorpattern.match(line)
+    if m1:
+        name = m1.group('scheme') + '(' + m1.group('name') + ')'
+        return name, [], None, None
     m1 = callnameargspattern.match(line)
     if m1:
         return m1.group('name'), m1.group('args'), None, None
@@ -1151,6 +1166,9 @@ def analyzeline(m, case, line):
                     continue
             else:
                 k = rmbadname1(m1.group('name'))
+            if case in ['public', 'private'] and \
+               (k == 'operator' or k == 'assignment'):
+                k += m1.group('after')
             if k not in edecl:
                 edecl[k] = {}
             if case == 'dimension':
@@ -1193,6 +1211,9 @@ def analyzeline(m, case, line):
         groupcache[groupcounter]['vars'] = edecl
         if last_name is not None:
             previous_context = ('variable', last_name, groupcounter)
+    elif case == 'moduleprocedure':
+        groupcache[groupcounter]['implementedby'] = \
+            [x.strip() for x in m.group('after').split(',')]
     elif case == 'parameter':
         edecl = groupcache[groupcounter]['vars']
         ll = m.group('after').strip()[1:-1]
@@ -2105,7 +2126,8 @@ def analyzebody(block, args, tab=''):
         else:
             as_ = args
         b = postcrack(b, as_, tab=tab + '\t')
-        if b['block'] in ['interface', 'abstract interface'] and not b['body']:
+        if b['block'] in ['interface', 'abstract interface'] and \
+           not b['body'] and not b['implementedby']:
             if 'f2pyenhancements' not in b:
                 continue
         if b['block'].replace(' ', '') == 'pythonmodule':

numpy/f2py/tests/src/crackfortran/operators.f90

@@ -0,0 +1,49 @@
+module foo
+  type bar
+     character(len = 32) :: item
+  end type bar
+  interface operator(.item.)
+     module procedure item_int, item_real
+  end interface operator(.item.)
+  interface operator(==)
+     module procedure items_are_equal
+  end interface operator(==)
+  interface assignment(=)
+     module procedure get_int, get_real
+  end interface assignment(=)
+contains
+  function item_int(val) result(elem)
+    integer, intent(in) :: val
+    type(bar) :: elem
+
+    write(elem%item, "(I32)") val
+  end function item_int
+
+  function item_real(val) result(elem)
+    real, intent(in) :: val
+    type(bar) :: elem
+
+    write(elem%item, "(1PE32.12)") val
+  end function item_real
+
+  function items_are_equal(val1, val2) result(equal)
+    type(bar), intent(in) :: val1, val2
+    logical :: equal
+
+    equal = (val1%item == val2%item)
+  end function items_are_equal
+
+  subroutine get_real(rval, item)
+    real, intent(out) :: rval
+    type(bar), intent(in) :: item
+
+    read(item%item, *) rval
+  end subroutine get_real
+
+  subroutine get_int(rval, item)
+    integer, intent(out) :: rval
+    type(bar), intent(in) :: item
+
+    read(item%item, *) rval
+  end subroutine get_int
+end module foo

numpy/f2py/tests/test_crackfortran.py

@@ -45,6 +45,26 @@ def test_defaultPublic(self, tmp_path):
         assert "public" in mod["vars"]["seta"]["attrspec"]
 
 
+class TestModuleProcedure():
+    def test_moduleOperators(self, tmp_path):
+        fpath = util.getpath("tests", "src", "crackfortran", "operators.f90")
+        mod = crackfortran.crackfortran([str(fpath)])
+        assert len(mod) == 1
+        mod = mod[0]
+        assert "body" in mod and len(mod["body"]) == 9
+        assert mod["body"][1]["name"] == "operator(.item.)"
+        assert "implementedby" in mod["body"][1]
+        assert mod["body"][1]["implementedby"] == \
+            ["item_int", "item_real"]
+        assert mod["body"][2]["name"] == "operator(==)"
+        assert "implementedby" in mod["body"][2]
+        assert mod["body"][2]["implementedby"] == ["items_are_equal"]
+        assert mod["body"][3]["name"] == "assignment(=)"
+        assert "implementedby" in mod["body"][3]
+        assert mod["body"][3]["implementedby"] == \
+            ["get_int", "get_real"]
+
+
 class TestExternal(util.F2PyTest):
     # issue gh-17859: add external attribute support
     sources = [util.getpath("tests", "src", "crackfortran", "gh17859.f")]